Oh so maybe he's gone onto a standard economy 7 rate? Esther than a fixed lower rate?
Anyone here with experience of storage heaters? Need some info/advice?
- Thread starter NeilF
- Start date
Sounds like you may have identified the cause of those high bills!
I had storage heaters in a flat I had down south several years back (a large one in the living room and a small one in the hallway), they were rubbish and in the end I only ever used them on a lower setting to warm the flat in the mornings and bought two inexpensive oil-filled radiators (the kind you can move around) to use while I was actually at home.
Even on a high input setting with low output, they'd be cold by the time I got home from work in the afternoon/evenings.
I had storage heaters in a flat I had down south several years back (a large one in the living room and a small one in the hallway), they were rubbish and in the end I only ever used them on a lower setting to warm the flat in the mornings and bought two inexpensive oil-filled radiators (the kind you can move around) to use while I was actually at home.
Even on a high input setting with low output, they'd be cold by the time I got home from work in the afternoon/evenings.
I had storage heaters in my flat very similar to the ones you’ve posted here. Unfortunately the previous owner was a moron (and a sparky...) and had for some reason removed the separate feed needed to have an E7 tariff. Cue some swearing when checking electricity usage as they weren’t switching off during the day!
Eventually we ripped them out as they weren’t retaining heat well enough anyway and replaced them with normal panel heaters that are controllable. I think doing it this way is more expensive than properly setup (modern) storage heaters but infinitely easier to live with day to day.
The immersion we’ve found to be not too bad as we only need enough hot water for showers so just have it running for 90 minutes in the morning and 45 minutes just before we get home from work.
Eventually we ripped them out as they weren’t retaining heat well enough anyway and replaced them with normal panel heaters that are controllable. I think doing it this way is more expensive than properly setup (modern) storage heaters but infinitely easier to live with day to day.
The immersion we’ve found to be not too bad as we only need enough hot water for showers so just have it running for 90 minutes in the morning and 45 minutes just before we get home from work.
That sounds very logical... Unfortunately the immersion in this case is on the night ciruit, so runs for 7hrs overnight, meaning come late afternoon, no hot water!
Soldato
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It doesn’t run for the full 7 hours the element has a thermostat on it that shuts it off after the water is up to the set temperature.
Most tanks on economy 7 have two elements with one on day circuit the other on nights so you can use the day time one during the day to top it up if required.
Understood, but clearly running for 7 hours even with a thermostat overnight is daft, when running from 5-6:30 would achieve the same, for less power.
Yes, there are two circuits and two thermostats to the tank in question. But just have on/off buttons though. ie: No timers to be more efficient etc.
While technically correct there is more nuance to it than just putting it in for 90mins.
It depends on the size of the cylinder, how much it needs to reheat daily and the size of the heating element. There will be some losses from the tank it’s self but they’ll be very small on a modern cylinder. That’s why people say just leave it on for the E7 period and you’ll know you’ll never under heat it when it costs way more to boost it during the day.
Alternatively work out what is the maximum time it would need to reheat it from cold and set it for that.
understood, but at the moment with the water being heated 7hrs by economy 7, the water is no longer hot from late afternoon.
That may be something to do with how well your water cylinder is insulated. Like your loft the more insulation the longer the water will stay hot for.
Never the less their is no need to heat your water tank up all night, set it to come on 1-2 hours before he gets up, that way you are eliminating heat loss throughout the night when you are not using hot water. You may need to experiment a little to find the sweet spot but we set it to come on an hour an a half before the rate changes which works for us.
Think of a HWC as a heat store, not a hot water store.
What I did to mine many years ago was install a thermostatic mixing valve in the outlet to the E7 HWC to limit the hot water outlet temp to a safe level, but then set the actual immersion heaters to nearer 90C. This near enough doubles the amount of heat the HWC can store
I have not had to use a daytime top up ever. And indeed can get away with only operating the heater 3 days a week.
However, it is inadvisable to do this without a mixing valve in place. At best you will crack your wash basins, at worst risk being badly scalded (Or have unaware guests and visitors badly scalded)
Also, this strategy should only be attempted with an old fashioned vented HWC. Not sure what happens in an unvented cylinder if the water actually boils. I imagine it is supposed to have a safety relief but I am not sure how effective it is in practice.
Water boiling in a vented cylinder is quite amusing, Lots of rumbles and the hot water all ends up in the cold water tank.
I'd look at the thermal efficiency of the cylinder its self, is it old?
In my last house we had a fairly modern (but not the newest version of a) megaflow unvented cylinder and the water was still hot after 2 days (assuming you didn't use all the hot water...). We only used to heat it once a day. If it's no longer hot by mid afternoon its either undersized and therefore doesn't hold enough hot water or its letting all the heat out.
Is the cupboard where its contained warmer than the rest of the house?
Soldato
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So you have a total of 1700 x 3 + 2550. This is 5,355 W of heating capacity there. If that runs on full for 7 hours it has used 5355 x 7 = over 37 kWh. At 11p per kWh that would be over £4.
So I assume you are happy that the numbers are correct?
I had storage heaters in a flat years ago, they are terrible to control properly.